The work proposed for the 07 year of this research grant will be approximately equally divided between clinico-pathologic studies of several different human renal diseases and of 2 or 3 different experimental models. In man, work is being conducted and will continue particularly on specific aspects of lupus nephritis,myeloma kidney, crescenteric glomerulonephritis, polyarteritis nodosa and sarcoidosis. In the experimental animal, the planned research will concentrate primarily on: (1) Study of various factors, such as hydropenia, acidosis and hypercalcemia, which may aggravate the Bence Jones cast nephropathy model previously developed in our laboratory and (2) the effect(s) of dietary hyperlipidemia as an aggrevating factor on the focal glomerulosclerosis induced in rats by repeated injections of aminonucleoside and on the vascular lesions of spontaneously hypertensive rats. Morphologically, both human and experimental studies are based on detailed light-, electron, and immunofluorescence- and immunoperoxidase-microscopic evaluation of single or sequential renal biopsies. Appropriate laboratory and functional methods will be correlated with the morphologic findings in an attempt to gain better understanding of the functional and clinical significance of the different types of lesions detected in the kidneys.